I think the show gets better and better over the seasons. The plot usually revolves around some recent occurrence, so it stays up to date. Being able to relate to the episodes in this way makes the show really amusing.

That's what I fucking hate about the newer episodes, they rely on pop culture and news references instead of just being funny. They used to have references that were more subtle or became their own thing (sexual harassment panda) instead of just being like LOOK THIS IS IN THE NEWS HAHAHA